I don't see the problem. Using the threat of eternal hell to manage occasional little annoyances is certainly abusive. That is - it's abusive when the parent routinely uses tis tactic. Just as it's abusive when bad parents routinely swat their kids about the head.

Horrible as it is to see children taught to believe in hell, it's not abuse when the parent believes it, when the parent is honestly trying to protect their kids from something they think is a terrible and real danger.